1. Field of the Invention
This invention relates to improvements in door locking devices, and more particularly, but not by way of limitation, to a security lock device operable from one side of the door only, and having quick release means for facilitating opening of the door, particularly under panic conditions, or the like.
2. Description of the Prior Art
It is the usual practice in many building constructions, particularly in industrial buildings, such as warehouses, factories, and the like, to provide access doors disposed in areas remotely disposed with respect to the usual or normal entry doors. For example, rear or side doors are frequently provided in large buildings for facilitating evacuation of the building, or permitting leaving of the building for any reason. However, it is usually important to prevent entry of the building through these remote doors by unauthorized personnel, and locking of the doors in a manner precluding entry from the exterior of the building is extremely important. Security locks have been devised for use on doors of this type. However, many of the locking devices are not efficient in that they may be tampered with from the exterior of the door in such a manner as to permit unwanted opening of the door. In addition, many of these locks require keys, or the like, for releasing the locking elements, even from the interior of the building, and this frequently renders the door very difficult to open by the normal personnel working within the building, which is a safety hazard. Under panic conditions, such as a fire, or other catastrophe, it is important that the locked door may be readily opened by the personnel in order to permit evacuation of the building.